1. Field of the Invention
This invention generally relates to an apparatus and method for switching a light source by using a light sensor. And especially to an apparatus and method for switching a light source by using a light sensor to judge whether or not a light source should be activated.
2. Description of Related Art
In the conventional keyboard of a mobile telephone, light emitting diode (i.e. LED) is generally utilized for the background light design. In addition, the lighting time and occasion are fixed regardless under sun light or in a dark room. However, when a user is in a sufficient light environment, it is not necessary to have the background light LED of the keyboard activated. Since the LED is not switched off at the time, the mobile telephone consumes a great amount of power. The communication time and standby period of the mobile telephone are therefore affected. Nowadays, due to the design trend of a mobile phone being light, thin and small, the volume and capacity of the battery can not be unlimitedly increased. The prior art fixed light emitting method is disadvantageous in the aspect of power consumption.
Accordingly, we need a better method to solve the above-mentioned problem so as to avoid power waste under the sufficient light environment.